The present invention is directed to hydraulic systems and particularly to a sequential control system operative to cause the operation of a plurality of motors in sequence.
Modern earth-working machines normally include a number of earth-working implements, each operated by its own control system by separate control valves, each of the separate control valves normally operated by means of a separate control lever. In many instances the efficiency of the operator of the machine and the output of the machine can be greatly increased by combining separate work functions into a single hydraulic circuit so that, for example, two work functions are performed automatically by the same control lever at a preset sequence. One example of a machine that could be improved in this manner is a loader having an ejector bucket. Such loaders normally employ a hydraulically actuated ejector bucket where the bucket is racked forward to a dump position with one or more hydraulic jacks, while a second hydraulic jack is employed for moving the ejector forward. After the bucket is emptied, the ejector is retracted and the bucket is racked back to its loading position.
Other types of machines having such a preset sequence of operation could also advantageously employ such a control system for sequential operation as is herein proposed.